Field
1. This invention is directed to an apparatus for burning sulfur to sulfur dioxide, which sulfur dioxide is then used to generate sulfurous acid.
State of the Art
2. Various small sulfur burning sulfur dioxide generators are known, such as those described in U.S. Pat. Nos. 3,226,201, 3,337,989, 3,627,134, 3,907,510 and 4,039,289. These devices are limited in the maximum burning rate of sulfur per hour to approximately 7 pounds of sulfur per hour per square foot of burning surface. Assignee devised a Sulfurous Acid Generator, U.S. Pat. No. 4,526,771 utilizing a positive pressure air feed system which significantly increased the sulfur burn rate and efficiency, but did not provide sufficient ability to provide varying strengths of acids required by farmers for differing agricultural applications. Because of the positive air pressure oxygen feed system, applicant's previous invention was subject to sulfur dioxide leaks through breaks in seals, and machine welds which could jeopardize the operator. The heat produced from burning sulfur was not recaptured, but dissipated into the atmosphere. The present invention eliminates these deficiencies, as more fully described below.